Magnetic tape data cartridges have the capability for high data capacity and are easily and convenient to use for many computer applications. Computer equipment using such data cartridges are equipped with a tape drive system or assembly that accepts the cartridges, positions them for reading or recording, and permits removal of the cartridges. The data cartridge drive system has become accepted as a utilitaian storage system by major portions of the computer industry. Not only are computer systems becoming cartridge-equipped, but so are a great many auxiliary and supportive devices.
Data cartridges supply good performance and reliability. Data cartridge design permits accurate reading and writing of digital data, repetively and rapidly. Total encapsulation of tape in the cartridge provides superior tape protection from dropout producing dust, debris and fingerprints. Rigid base plate, captive and controlled enclosure of tape and precise tape guidance system assure excellent mechanical alignment. Size, packaging and design combine to make this medium tolerant to the potentially rougher care by users unskilled in handling computer media and in less-than-ideal environment conditions.
The following types of systems--minicomputers for machine control, data logging for sensor-based systems, word processing, key-to-tape storage for terminals, source data in inventory control--all have one functional need in common, i.e., a removable storage system. Further, general requirements for these systems are that the data storage media be small, inexpensive, interchangeable, and easily inserted in a lowcost drive.
Typical magnetic tape data cartridges, such as the DC 100A and DC 300A 3M Company data cartridges have the capability of high data capacity, are compact in size, have compact drive assemblies, are reliable and are easy and convenient to use for many data processing and data storage and retrieval applications such as computer mass storage. The physical dimensions of such data cartridges have been standardized. Computer and other data processing equipment using such data cartridges are equipped with a tape drive that accepts insertion of a data cartridge, positions the data cartridge for reading or recording, and allows removal of the data cartridge in order to make the tape drive available for another interchangeable data cartridge. The tape drive assembly must provide repeated reliable interface with the data cartridge both mechanically and electrically.
Known data cartridge tape drives are dificient for reliably and repeatedly mechanically positioning the data tape cartridge for good electrical interface, i.e., reading and recording of data, or if they do positively position the cartridge, the cartridge is difficult to remove from the tape drive because of the high holding force used for secure positioning. Some tape drive designs provide a locking force release device that is actuated by a push button. The mechanism of such a locking force release device adds to the size, cost, and complexity of the design.
Thus, it would be desirable to have a simple tape drive assembly for data cartridges that would positively, repeatedly, and reliably position the data cartridge in a simple manner for accurate mechanical and electrical interface with the tape drive while maintaining the ease of inserting and removing the data cartridge.